Search Results (889)

Additive manufacturing has been adopted in several industries including the medical field to develop new personalised medical implants including tissue engineering scaffolds. Custom patient-specific scaffolds can be additively manufactured to speed up the wound healing process. The aim of this study was to design, fabricate, and evaluate a range of materials and scaffold architectures for 3D-printed wound dressings intended for soft tissue applications, such as skin repair. Multiple biocompatible polymers, including polylactic acid (PLA), polyvinyl alcohol (PVA), butenediol vinyl alcohol copolymer (BVOH), and polycaprolactone (PCL), were fabricated using a material extrusion additive manufacturing technique. Eight scaffolds, five with circular designs (knee meniscus angled (KMA), knee meniscus stacked (KMS), circle dense centre (CDC), circle dense edge (CDE), and circle no gradient (CNG)), and three square scaffolds (square dense centre (SDC), square dense edge (SDE), and square no gradient (SNG), with varying pore widths and gradient distributions) were designed using an open-source custom toolpath generator to enable precise control over scaffold architecture. An in vitro degradation study in phosphate-buffered saline demonstrated that PLA exhibited the greatest material stability, indicating minimal degradation under the tested conditions. In comparison, PVA showed improved performance relative to BVOH, as it was capable of absorbing a greater volume of exudate fluid and remained structurally intact for a longer duration, requiring up to 60 min to fully dissolve. Tensile testing of PLA scaffolds further revealed that designs with increased porosity towards the centre exhibited superior mechanical performance. The strongest scaffold design exhibited a Young’s modulus of 1060.67 ± 16.22 MPa and withstood a maximum tensile stress of 21.89 ± 0.81 MPa before fracture, while maintaining a porosity of approximately 52.37%. This demonstrates a favourable balance between mechanical strength and porosity that mimics key properties of engineered tissues such as the meniscus. Overall, these findings highlight the potential of 3D-printed, patient-specific scaffolds to enhance the effectiveness and customisation of tissue engineering treatments, such as meniscus repair, offering a promising approach for next-generation regenerative applications. Full article

Bacterial infections remain a major challenge to human health, especially in wound healing, where they can cause prolonged inflammation, delayed recovery, and severe complications. Current research is increasingly focused on developing innovative antimicrobial materials capable of overcoming the limitations of conventional antibiotics, whose effectiveness has declined due to the rise in bacterial resistance. Among the various alternatives, silver nanoparticles have gained particular attention for their broad-spectrum antibacterial properties and have already been successfully applied in the functionalization of commercial wound dressings. The aim of this study was to optimize the functionalization of commercial cotton gauzes based on in situ UV-assisted reduction of silver nanoparticles, reducing methanol usage and identifying the minimal silver nitrate precursor concentration to achieve antimicrobial efficacy while maintaining biocompatibility. Different precursor concentrations were then evaluated through cytocompatibility assays (MTT, Live/Dead, and scratch tests on fibroblasts) and antimicrobial analyses against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus (including an antibiotic-resistant strain), and Candida albicans. The results demonstrated that a 0.5% w/w silver nitrate concentration provided strong antimicrobial and antibiofilm activity without compromising textile properties or cytocompatibility. Furthermore, this optimized process reduced material waste, highlighting its potential for scalable production of antimicrobial wound dressings. Full article

Wound dressing coverages (WDC) play a key role in protecting skin lesions and preventing infection. Polymeric membranes have been widely explored as WDC due to their ability to incorporate bioactive agents, including antimicrobial nanoparticles and non-steroidal anti-inflammatory drugs (NSAIDs). In this study, polycaprolactone (PCL)-based membranes functionalized with titanium dioxide nanoparticles (TiO₂ NPs) and ibuprofen (IBP) were fabricated using a film manufacturing approach, and their structural and biocompatibility profiles were evaluated. The membranes were characterized by SEM, FTIR and XPS. Bands at 1725 cm⁻¹, 2950 cm⁻¹, 2955 cm⁻¹, 2865 cm⁻¹ and 510 cm⁻¹ proved molecular stability of reagents during manufacture. In SEM, the control shows the flattest surface, while the PCL-IBP and PCL-IBP-TiO₂ NPs groups had increased rugosity. In vitro biocompatibility was evaluated using human fetal osteoblasts (hFOB). On day 3, the cell adhesion response of hFOB seeded in PCL-IBP and PCL-IBP-TiO₂ NPs groups showed the biggest absorbances (p = 0.0014 and p = 0.0491, respectively). On day 7 PCL-IBP group had lower lectin binding than the control (p = 0.007) and the PCL-IBP-TiO₂ NPs (p = 0.015) membranes, but no evidence of cytotoxicity was observed in any group. Furthermore, the Live/Dead test adds more biocompatibility evidence to conveniently discriminate between live and dead cells. The PCL polymeric membrane elaborated in this study may confer antiseptic, analgesic and anti-inflammatory properties, making these membranes ideal for skin lesions. Full article

Integrating antibacterial fabrics into wearable technology represents a transformative advancement in healthcare, fashion, and personal hygiene. Antibacterial fabrics, designed to inhibit microbial growth, are gaining prominence due to their potential to reduce infections, enhance durability, and maintain cleanliness in wearable devices. These fabrics offer effective antimicrobial properties while retaining comfort and functionality by incorporating nanotechnology and advanced materials, such as silver nanoparticles, zinc oxide, titanium dioxide, and graphene. The production techniques for antibacterial textiles range from chemical and physical surface modifications to biological treatments, each tailored to achieve long-lasting antibacterial performance while preserving fabric comfort and breathability. Advanced methods such as nanoparticle embedding, sol–gel coating, electrospinning, and green synthesis approaches have shown significant promise in enhancing antibacterial efficacy and material compatibility. Wearable technology, including fitness trackers, smart clothing, and medical monitoring devices, relies on prolonged skin contact, making the prevention of bacterial colonization essential for user safety and product longevity. Antibacterial fabrics address these concerns by reducing odor, preventing skin irritation, and minimizing the risk of infection, especially in medical applications such as wound dressings and patient monitoring systems. Despite their potential, integrating antibacterial fabrics into wearable technology presents several challenges. This review provides a comprehensive overview of the key antibacterial agents, the production strategies used to fabricate antibacterial textiles, and their emerging applications in wearable technologies. It also highlights the need for interdisciplinary research to overcome current limitations and promote the development of sustainable, safe, and functional antibacterial fabrics for next-generation wearable. Full article

Biomaterials derived from natural-origin polymers often lack the desired functionality and additional features, such as antibacterial properties, which could be beneficial in the design of modern wound dressings. Our research aimed to fabricate biosafe antibacterial dressings through the modification of curdlan-based hydrogels with triangle-shaped silver nanoparticles (AgTNPs) and poly(L-DOPA) (PL). The prepared hydrogels, including physicochemical, structural, biological, and antibacterial assessments, were thoroughly characterized. All formulations were confirmed to be non-toxic toward eukaryotic cells. The presence of PL in the hydrogels significantly reduced mortality in the zebrafish larvae model, highlighting the improved biocompatibility of the hydrogels. The three-component hydrogel (CUR-PL-AgT) demonstrated a high antibacterial effectiveness against Staphylococcus aureus and Pseudomonas aeruginosa. Additionally, the same three-component material outperformed a hydrogel containing only AgTNPs in promoting blood clot formation. Furthermore, PL enhanced the heat generating capability of hydrogels, showing their potential in medical applications where the temperature effects can stimulate biological processes of different natures. Full article

Systemic anticancer therapy causes a number of side effects; therefore, local drug release devices may play an important role in this area. In this study, we developed polyurethane-dendrimer foams containing different amounts of third-generation poly (amidoamine) dendrimers (PAMAM G3) to evaluate their ability to encapsulate and release the model anticancer drug doxorubicin (DOX), as well as their biocompatibility and effectiveness against normal and cancer cells in vitro. PU–PAMAM foams containing 10–50 wt% PAMAM G3 were prepared using glycerin-based polyether polyol and castor oil as co-components. Structural and rheological analyses revealed that foams containing up to 20 wt% PAMAM G3 exhibited a well-developed porous structure, while higher dendrimer loadings (≥30 wt%) led to irregular cell shapes, pore coalescence, and thinning of cell walls, and indicated a gradual loss of structural integrity. Rheological creep–recovery measurements confirmed the structural findings: moderate PAMAM G3 incorporation (≤20 wt%) increased both the instantaneous and delayed elastic modulus (E₁ ≈ 130–140 kPa; E₂ ≈ 80 kPa) and enhanced elastic recovery, reflecting improved cross-link density and foam stability. Higher dendrimer contents (30–50 wt%) caused a decline in these parameters and higher viscoelastic compliance, indicating a softer, less stable structure. The DOX loading capacity and encapsulation efficiency increased with PAMAM G3 content, reaching maximum values of 35% and 51% for 30–40 wt% PAMAM G3, respectively. However, the most sustained DOX release profiles were observed for matrices containing 20 wt% PAMAM G3. Analysis of cumulative release and kinetic modeling revealed a transition from diffusion-controlled release at low PAMAM contents to burst-dominated release at higher dendrimer loadings. Importantly, matrices containing 10–20 wt% PAMAM G3 also indicated selective anticancer action against squamous cell carcinoma (SCC-15) compared to non-cancerous human keratinocytes (HaCaT). Moreover, the DOX they released effectively destroyed cancer cells. Overall, PU–PAMAM foams containing 10–20 wt% PAMAM G3 provide the most balanced combination of structural stability, controlled drug release, and cytocompatibility. These materials therefore represent a promising platform as passive carriers in drug delivery systems (DDSs), such as local implants, anticancer patches, or bioactive wound dressings. Full article

To address the challenges in wound healing, clinical management increasingly demands targeted, adaptive, responsive, and patient-centered strategies. This is especially true for wounds characterized by delayed healing and a high risk of infection. Advances in regenerative medicine and biomaterial technologies are fostering the development of multifunctional approaches that integrate tissue regeneration, antibacterial/antibiofilm activity, immunomodulation, and real-time monitoring. This paper surveys emerging platforms, including both natural and synthetic scaffolds, hydrogels enriched with platelet-derived growth factors, glycosaminoglycan mimetics, bioactive peptides (such as GHK-Cu and antimicrobial peptides), nanoscaffolds, and stimuli-responsive systems. The paper also explores cutting-edge technologies such as water-powered, electronics-free dressings that deliver localized electrical stimulation; biodegradable bioelectric sutures that produce self-sustained mechano-electrical signals; and sensory bandages that monitor pH, moisture, temperature, and bacterial contamination in real-time while enabling on-demand drug release with pro-regenerative, antibacterial, and other therapeutic functionalities. Further therapeutic approaches include natural matrices, exosomes, gene editing, 3D bioprinting, and AI-assisted design. Particular attention is paid to orthopedic applications and orthopedic implant infection. A brief section addresses the still unresolved challenge of articular cartilage regeneration. Interdisciplinary innovation, integrating insights from molecular biology through engineering, plays a central role in translating novel strategies into tailored, clinically effective wound management solutions. Full article

Chronic and complex wounds require biomaterials that are both cytocompatible and antimicrobial. Herein, electrospun polycaprolactone (PCL) nanofiber membranes were coated with Type I collagen and functionalized with silver nanoparticles (AgNPs). The main objective was to assess fibroblast adhesion, proliferation, and cytotoxicity. Membrane morphology and surface characteristics were analyzed in a previous work by SEM, AFM, and wettability measurements, confirming the transformation from hydrophobic PCL to fully wettable collagen-coated surfaces. In this study, Murine 3T3 fibroblasts were cultured on PCL, PCL–Collagen, PCL–Collagen–Citrate, and PCL–Collagen–AgNPs membranes. Cellular activity was quantified using Alamar Blue assays at 24, 48, and 72 h, while cytotoxicity was determined by LDH release. Cellular viability and adhesion were studied using confocal microscopy. All membrane types supported fibroblast growth, with collagen-coated samples exhibiting the highest metabolic activity. AgNPs-functionalized membranes sustained overall cell viability above 90%, with cytotoxicity values of approximately 10% at 24 h and 20% at 48 h. Antimicrobial evaluations demonstrated complete inhibition of Pseudomonas aeruginosa and vancomycin-resistant Enterococcus, and partial inhibition of Staphylococcus aureus. These results indicate that collagen-coated, AgNPs-functionalized electrospun PCL membranes exhibit both high cytocompatibility and significant antimicrobial activity, supporting their potential as advanced wound-dressing materials. Full article

Electrospun polymeric nanofibers have emerged as promising materials for wound management owing to their high surface area, efficient exudate absorption and gas exchange, and extracellular-matrix-like architecture. This study investigates the fabrication of nanofiber dressings from poly(vinyl alcohol) (PVA) and hyaluronic acid (HA), prepared by fully aqueous electrospinning (without organic solvents) for potential wound-care applications. HA incorporation is expected to influence hydration and matrix interactions, properties that have been associated with modulation of wound healing in previous studies. However, the high solubility of PVA-based NFs in aqueous environments limits their use in biological applications. To address this issue, PVA/HA nanofibers were chemically crosslinked through a solid-state esterification process at 150 °C using biocompatible citric acid (CA). The electrospinning parameters were optimized to obtain PVA/HA fibers with diameters ranging from 130 to 200 nm, which were assembled to form mats with different porosity and intersection density. FTIR confirmed the formation of ester bonds, while DSC analysis showed an increase in Tg from 41 °C to about 55 °C and a slight decrease in Tm after crosslinking. Swelling and degradation analyses demonstrated a significant enhancement in hydrolytic stability, as the weight loss of the nanofiber mats decreased from ~90% in the non-crosslinked samples to less than 10% after 2 h of crosslinking. Dynamic mechanical analysis (DMA) showed an increase in Young’s modulus from ~70 MPa to 230 MPa after crosslinking. Overall, the results demonstrate the stabilizing effect of citric-acid crosslinking on PVA/HA nanofibers and support their potential use in wound dressings under physiological conditions. Full article

Disorders of skin wound healing and the repair of full-thickness skin defects remain significant clinical challenges. Natural polysaccharide-based hydrogels, with their excellent biocompatibility, tunable degradability, and multifunctional properties (e.g., antibacterial, antioxidant, and pro-angiogenic), have emerged as key materials for designing wound dressings and skin tissue engineering scaffolds. This review systematically summarizes recent advances in polysaccharide hydrogels—including chitosan, hyaluronic acid, and alginate—focusing on material types, crosslinking strategies, and functional modifications, with particular emphasis on their dual applications in wound healing (acute and chronic wounds) and skin tissue engineering. In wound healing, these hydrogels regulate the microenvironment through multiple mechanisms, including anti-inflammatory, antioxidant, pro-angiogenic, and immunomodulatory effects. In skin tissue engineering, their three-dimensional porous structures mimic the extracellular matrix, supporting cell adhesion, proliferation, and tissue regeneration. Finally, we discuss the challenges and future prospects for the clinical translation and commercialization of natural polysaccharide hydrogels. Full article

Temperature-responsive hydrogels are sophisticated stimuli-responsive biomaterials that undergo rapid, reversible sol–gel phase transitions in response to subtle thermal stimuli, most notably around physiological temperature. This inherent thermosensitivity enables non-invasive, precise spatiotemporal control of material properties and bioactive payload release, rendering them highly promising for advanced biomedical applications. This review critically surveys recent advances in the design, synthesis, and translational potential of thermo-responsive hydrogels, emphasizing nanoscale and hybrid architectures optimized for superior tunability and biological performance. Foundational systems remain dominated by poly(N-isopropylacrylamide) (PNIPAAm), which exhibits a sharp lower critical solution temperature near 32 °C, alongside Pluronic/Poloxamer triblock copolymers and thermosensitive cellulose derivatives. Contemporary developments increasingly exploit biohybrid and nanocomposite strategies that incorporate natural polymers such as chitosan, gelatin, or hyaluronic acid with synthetic thermo-responsive segments, yielding materials with markedly enhanced mechanical robustness, biocompatibility, and physiologically relevant transition behavior. Cross-linking methodologies—encompassing covalent chemical approaches, dynamic physical interactions, and radiation-induced polymerization are rigorously assessed for their effects on network topology, swelling/deswelling kinetics, pore structure, and degradation characteristics. Prominent applications include on-demand drug and gene delivery, injectable in situ gelling systems, three-dimensional matrices for cell encapsulation and organoid culture, tissue engineering scaffolds, self-healing wound dressings, and responsive biosensing platforms. The integration of multi-stimuli orthogonality, nanotechnology, and artificial intelligence-guided materials discovery is anticipated to deliver fully programmable, patient-specific hydrogels, establishing them as pivotal enabling technologies in precision and regenerative medicine. Full article

Injectable hydrogels (IHs) have gained considerable interest in biomedical and aesthetic applications due to their minimally invasive delivery, selective localization, and sustained release of bioactive agents. They exhibit flowability during administration and undergo in situ gelation under physiological conditions. These behaviors are influenced by their tunable structural, physical, mechanical, and viscoelastic properties, modulating performance. Rheological parameters, including viscosity (η), storage modulus (G′), loss modulus (G″), and yield stress (τ_y) of IHs with time (t), shear rate ($\stackrel{·}{\gamma }$), and frequency (f), explaining their shear thinning, thixotropy, viscoelasticity, and gelatin kinetics, serve as key quantitative indicators of their injectability, self-healing capability, and structural and mechanical stability. The rheological characteristics reflect molecular interactions and crosslinking mechanisms within IH networks, thereby linking formulation to provide overall performance, including injectability, biodegradability, and controlled release. This review summarizes recent advances in IHs for diverse applications, with a primary focus on their rheological properties. It also briefly addresses their composition, intermolecular interactions, and correlated function and performance. The applications discussed include hemostatic and wound dressings, tissue engineering and regenerative medicine scaffolds, drug delivery systems, reconstructive and aesthetic materials, and functional bioinks for 3D printing. Overall, this review demonstrates that rheological characterization provides an essential framework for the rational engineering of next-generation IH systems. Full article

This study introduces a composite method that integrates a diamond-coated tubular grinding electrode with short electric arc machining (SEAM) for GH4099. Mechanical micro-grinding and arc erosion act concurrently within the inter-electrode gap, enabling an in situ “erode–dress” coupling in which the grinding action levels nascent craters and promotes debris evacuation while SEAM supplies localized thermal–electrical energy for removal. A design-of-experiment scheme probes discharge and grinding factors, and performance is evaluated by material removal behavior, electrode wear, and surface integrity. Within a robust window (12–24 V; 500–2000 r/min), the composite process sustains stable discharges without catastrophic melting at 24 V and yields dense, uniform textures. Representative surfaces show controllable areal roughness (Sa ≈ 14–27 µm across 80#–600#), reflecting a practical finishing–efficiency trade-off. Multi-scale characterization (3D topography, cross-sectional metallography, SEM) evidences suppression of recast steps, macro-protrusions, and irregular pits, with more evenly distributed, shallower grinding traces compared to those with single-mode SEAM. The comparative analyses clarify discharge stabilization and recast-layer mitigation mechanisms, establishing a feasible pathway to high-quality, high-efficiency composite SEAM of GH4099 without resorting to overly aggressive electrical conditions. Full article

Background: Postoperative abdominal adhesions are a common and serious complication following abdominal surgery, often leading to chronic pain, bowel obstruction, or infertility. This study aimed to evaluate the efficacy of the new starch-based absorbable hemostatic agent and dressing, BioSight, in comparison with a predicate device (4DryField^® PH) for the prevention of abdominal adhesions in a rat model. Methods: A total of 90 Sprague–Dawley rats were used to establish an intra-abdominal adhesion model and assigned to the BioSight, 4DryField^® PH, or control group. Standardized injuries were created on the cecum and parietal peritoneum, followed by application of the designated materials. Animals were sacrificed at 2, 4, and 12 weeks for macroscopic adhesion scoring and histopathological evaluation. Adhesion area, adhesion strength, and tissue thickness were assessed using established scoring systems, and local healing was examined by H&E staining. All quantitative data were analyzed using one-way ANOVA. Conclusions: In a rat peritoneal adhesion model, BioSight exhibited pronounced anti-adhesion efficacy comparable to 4DryField^® PH. Macroscopic evaluation showed consistently low adhesion scores (≤0.4) across all time points up to 12 weeks, while histological analysis confirmed reduced adhesion thickness, with BioSight displaying numerically lower values, particularly at early stages (251.3 ± 137.4 µm vs. 323.2 ± 174.6 µm at Week 2). This performance is attributed to rapid in situ hydrogel formation that provides effective temporary tissue separation, limits early fibrin deposition and inflammatory cell infiltration, and supports hemostasis. Importantly, the starch-based hydrogel exhibits a balanced biodegradation profile—persisting long enough to protect injured tissues during the critical inflammatory and fibroproliferative phases, yet undergoing complete enzymatic resorption thereafter without adverse tissue reactions. Collectively, these results highlight the anti-adhesion functionality of BioSight and support the clinical potential of plant-derived starch-based bioresorbable surgical adjuncts. Full article

As one of the most widely used synthetic polymer materials globally, polyvinyl alcohol (PVA) has exhibited promising application potential, especially in the field of wound dressing. Biomass-derived PVA was successfully developed to address the challenges of non-renewable resource depletion and environmental health risks associated with traditional fossil-derived PVA production. However, a knowledge gap still exists regarding the differences between biomass-derived and fossil-derived PVA in terms of their physicochemical and biocompatible properties for wound dressing. This study demonstrated that biomass-derived PVA not only retained the favorable biosafety of conventional PVA (exhibiting no cytotoxicity across multiple cell lines and no induction of inflammatory factors), but also exhibited superior physicochemical properties essential for wound dressing without adding other chemical reagents. Specifically, the light transmittance of biomass-derived PVA hydrogel (>85%) significantly exceeded that of fossil-derived counterparts, highlighting its advantage for wound dressing. Furthermore, the adhesion force of biomass-derived PVA hydrogel to porcine skin was approximately four times that of fossil-derived PVA hydrogel, and the biomass-derived hydrogel exhibited superior drug-loading capacity and more efficient sustained drug release. These findings strongly validated the benefits and applicability of biomass-derived PVA in wound dressing, especially for addressing complex wounds necessitating both physical defense and drug-based intervention. Full article